1. Field of the Invention
The invention relates to a drive train of a motor vehicle, having an internal combustion engine with a crankshaft, a transmission connected downstream for driving at least one axle of the motor vehicle, and a starter generator assigned to the internal combustion engine.
2. Description of the Related Art
An electrically operated starter generator operates as a motor when starting the internal combustion engine and is suitable during operation of the drive train as a mild hybrid for driving the axle of the motor vehicle together with the internal combustion engine. In the generator mode, the starter generator is driven by the internal combustion engine and/or via the axle of the motor vehicle.
EP 1 079 085 A2 discloses a drive train of the type mentioned above and has a starter generator connected to the crankshaft of the internal combustion engine via a flexible drive mechanism configured as a belt drive. The belt drive also drives various auxiliary units of the internal combustion engine. However, due to the use of the belt drive, the crankshaft is not decoupled from tensile belt forces and weight loading.
U.S. Pat. No. 6,024,667 and DE 198 46 029 A1 describe mechanisms that are active in an infinitely variable manner in drive trains of motor vehicles, in the field of auxiliary units of an internal combustion engine.
DE 10 2009 001 147 A1 describes a drive train of a motor vehicle having an internal combustion engine, a retarder controller and an electric machine.
It is an object of the invention to provide a drive train where the components for transmitting the torque of the starter generator require only little space and, during starting, the crankshaft of the internal combustion engine is decoupled from tensile forces and weights as a consequence of the starting operation.